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Full-Text Articles in Physical Sciences and Mathematics

The Effects Of Climate On Radial Growth Of Disjunct Northern White Cedar (Thuja Occidentalis L.) In Virginia, Joshua A. Kincaid Oct 2017

The Effects Of Climate On Radial Growth Of Disjunct Northern White Cedar (Thuja Occidentalis L.) In Virginia, Joshua A. Kincaid

Virginia Journal of Science

Understanding the geographic range and growth of species is essential for effective land management in a landscape affected by anthropogenic activity and climate change. Climate change is expected to alter the distribution and growth of many tree species in eastern North America, including northern white cedar (Thuja occidentalis L.). This research examined the effects of climate on radial growth of T. occidentalis in disjunct populations south of its continuous range margin in eastern North America. A T. occidentalis tree-ring chronology was developed and examined for growth-climate interactions. Mean sensitivity of the T. occidentalis chronology was within the range of …


Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain Oct 2015

Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain

Virginia Journal of Science

The Virginia landscape supports a remarkable diversity of forests, from maritime dune woodlands, swamp forests, and pine savannas of the Atlantic Coastal Plain, to post-agricultural pine-hardwood forests of the Piedmont, to mixed oak, mesophytic, northern hardwood, and high elevation spruce-fir forests across three mountain provinces in western parts of the state. Virginia’s forests also have been profoundly shaped by disturbance. Chestnut blight, hemlock woolly adelgid, emerald ash borer, and other pests have caused declines or functional extirpation of foundation species. Invasive plants like multiflora rose, Oriental bittersweet, and Japanese stiltgrass threaten both disturbed and intact forests. Oaks and other fire-dependent …


Survey Of The Ectoparasites Of The Invasive Small Indian Mongoose (Herpestes Auropunctatus [Carnivora: Herpestidae]) On St. John, U.S. Virgin Islands, Kelsey L. Townsend, Karen E. Powers Oct 2014

Survey Of The Ectoparasites Of The Invasive Small Indian Mongoose (Herpestes Auropunctatus [Carnivora: Herpestidae]) On St. John, U.S. Virgin Islands, Kelsey L. Townsend, Karen E. Powers

Virginia Journal of Science

In March 2012, live trapping surveys were conducted for invasive small Indian mongoose (Herpestes auropunctatus) on St. John, U.S. Virgin Islands. Forty mongoose were sampled (31%, 9&) for ectoparasites, and cat fleas (Ctenocephalides felis) were discovered on 17 individuals. There was no difference in the number of ectoparasites per mongoose across age classifications (r = 0.109, P = 0.579). However, males had more cat fleas than females, even when mass was taken into account (males are generally heavier). Future behavioral studies may explain these sex differences. Although management suggestions from this research are limited, these …


Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall Apr 2014

Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall

Virginia Journal of Science

Phytoplankton composition from 16 Virginia lakes and reservoirs are discussed with emphasis on the dominant taxa, algal bloom producers, and potentially harmful species at these locations. This is a companion study to the more comprehensive publication regarding Virginia freshwater phytoplankton by Marshall (2013).


91st Annual Meeting Of The Virginia Academy Of Science: Proceedings May 2013

91st Annual Meeting Of The Virginia Academy Of Science: Proceedings

Virginia Journal of Science

Proceedings of the 91st Annual Meeting of the Virginia Academy of Science, held at Virginia Polytechnic Institute and State University, May 22-24, 2013.


Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall Jan 2013

Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall

Virginia Journal of Science

This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations. With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as meso- or eutrophic. Among the cyanobacteria were 6 known toxin producers (Anabaena circinalis, Anabaena spiroides, Aphanizomenon flos-aquae, Cylindrospermopsis raciborskii, Limnothrix redekei, and Microcystis aeruginosa). The study characterizes phytoplankton populations in these aging freshwater habitats taken from a large number …


2011 Meeting Missing Abstracts Oct 2011

2011 Meeting Missing Abstracts

Virginia Journal of Science

Abstracts not included in Virginia Journal of Science Volume 62, No. 1 and 2, presented at the 89th Annual Meeting of the Virginia Academy of Science, May 25-27, 2011, at the University of Richmond, Richmond VA.


Corrections To The Paper "Phytoplankton Productivity In The Tidal Regions Of Four Chesapeake Bay (Usa) Tributaries." Virginia Journal Of Science. 2007 58(4): 191-204, By K. K. Nesius, H. G. Marshall, And T.A. Egerton Apr 2010

Corrections To The Paper "Phytoplankton Productivity In The Tidal Regions Of Four Chesapeake Bay (Usa) Tributaries." Virginia Journal Of Science. 2007 58(4): 191-204, By K. K. Nesius, H. G. Marshall, And T.A. Egerton

Virginia Journal of Science

Necessary corrections associated with the paper "Phytoplankton productivity in the tidal regions of four Chesapeake Bay (USA) tributaries", originally published in Virginia Journal of Science Volume 58, Number 4, pages 191-204, in 2007, by K.K. Nesius, H.G. Marshall, and T.A. Egerton.


A Habitat Model For The Detection Of Two-Lined Salamanders At C. F. Phelps Wildlife Management Area, Fauquier And Culpeper Counties, Virginia, Jay Mcghee, Michael D. Killian Jan 2010

A Habitat Model For The Detection Of Two-Lined Salamanders At C. F. Phelps Wildlife Management Area, Fauquier And Culpeper Counties, Virginia, Jay Mcghee, Michael D. Killian

Virginia Journal of Science

Aquatic salamanders represent an important component of Virginia river watersheds, but despite potential declines, few specifics are known about their habitat preferences. We surveyed the habitats of the northern two-lined salamander and collected data on an array of habitat variables associated with the species. We used a logistic regression analysis to develop a model predicting its presence or absence for a given 50m-transect. Our final model incorporated the variation in stream depth and direction of stream flow and accounted for 25% of the variation in our data. We conclude that stream depth variation is an important feature of salamander habitat …


Phytoplankton Blooms: Their Occurrence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton Oct 2009

Phytoplankton Blooms: Their Occurrence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton

Virginia Journal of Science

Sporadic algal bloom development within a 10 year monitoring program in Virginia tidal tributaries of Chesapeake Bay is reviewed. These blooms were common events, characteristically producing a color signature to the surface water, typically short lived, occurring mainly from spring into autumn throughout different salinity regions of these rivers, and were produced primarily by dinoflagellates. The abundance threshold levels that would identify bloom status from a non-bloom presence were species specific, varied with the taxon's cell size, and ranged from ca. 10 to 104 cells mL-1. Among the most consistent sporadic bloom producers were the dinoflagellates Akashiwo …


First Records Of Hypleurochilus Geminatus And Centropristis Philadelphica From Chesapeake Bay, Aimee D. Halvorson Oct 2009

First Records Of Hypleurochilus Geminatus And Centropristis Philadelphica From Chesapeake Bay, Aimee D. Halvorson

Virginia Journal of Science

During the fall of 2007, Centropris philadelphica (rock seabass) and Hypleurochilus geminatus (Crested blenny) were collected from Chesapeake Bay. These captures are significant as they represent the first substantiated record of C. philadelphica from Chesapeake Bay and only the second and third validated records of H. geminatus. Additionally, the first record of H. geminatus from Chesapeake Bay was only recently recognized since the specimen had been previously misidentified as Parablennius marmoreus (seaweed blenny). The collection of seven individuals of H. geminatus in 2007, from two locations, indicates that the species may be resident within the Chesapeake Bay estuary.


Management And Social Indicators Of Soil Carbon Storage In A Residential Ecosystem, Midlothian, Va, Christopher M. Gough, Eliza A. Fritz Jan 2009

Management And Social Indicators Of Soil Carbon Storage In A Residential Ecosystem, Midlothian, Va, Christopher M. Gough, Eliza A. Fritz

Virginia Journal of Science

Soil carbon storage- defined here as carbon mass per unit ground area- is an important ecosystem service, sequestering carbon that might otherwise exist in atmospheric CO2 . Significant attention has focused on the effects that humans have on carbon cycling, but little is known about how human behaviors and attitudes relate to lawn carbon storage. The objectives of this study were to conduct household surveys in concert with soil carbon sampling in a 10-year-old exurban neighborhood near Richmond, Virginia to quantify differences in soil carbon storage between residential lawns and mixed pine-hardwood forest fragments, and to determine how lawn …


Virginia Junior Academy Of Science Awards, 2007 Jul 2007

Virginia Junior Academy Of Science Awards, 2007

Virginia Journal of Science

Virginia Junior Academy of Science Awards Presented During the 66th Annual Meeting at James Madison University, Harrisonburg, Virginia, May 23-25, 2007.


2007 Vas Meeting Best Student Papers Jul 2007

2007 Vas Meeting Best Student Papers

Virginia Journal of Science

List of award winning student papers by section from the 85th Annual Meeting of the Virginia Academy of Science, May 24-26, 2007, James Madison University, Harrisonburg, VA


Abstracts Of Papers, 85th Annual Meeting Of The Virginia Academy Of Science, May 24-26, 2007, James Madison University, Harrisonburg Va Jul 2007

Abstracts Of Papers, 85th Annual Meeting Of The Virginia Academy Of Science, May 24-26, 2007, James Madison University, Harrisonburg Va

Virginia Journal of Science

Full abstracts of the 85th Annual Meeting of the Virginia Academy of Science, May 24-26, 2007, James Madison University, Harrisonburg VA


Jeffress Research Grant - 2005 Apr 2007

Jeffress Research Grant - 2005

Virginia Journal of Science

Seven-page list of winners of the Jeffress Research Grant Awards for 2005.


Jeffress Research Grant Awards - 2006 Apr 2007

Jeffress Research Grant Awards - 2006

Virginia Journal of Science

List of winners of the Jeffress Research Grant Awards for 2006.


Minutes: Council Meeting Oct 2006

Minutes: Council Meeting

Virginia Journal of Science

Minutes of the VAS Council meeting Friday May 26, 2006, 8 - 9:40 AM, at Skelton Conference Center Inn, Virginia Tech, Blacksburg VA. Minutes were edited for publication.


Abstracts Of Papers, 84th Annual Meeting Of The Virginia Academy Of Science Apr 2006

Abstracts Of Papers, 84th Annual Meeting Of The Virginia Academy Of Science

Virginia Journal of Science

Full abstracts of papers for the 84th Annual Meeting of the Virginia Academy of Science, May 25-26, 2006, Virginia Polytechnic Institute and State University, Blacksburg, VA


Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Harold G. Marshall, Lubomira Burchardt Jul 2005

Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Harold G. Marshall, Lubomira Burchardt

Virginia Journal of Science

Phytoplankton composition and the range of seasonal patterns of abundance are presented for the tidal freshwater regions in two Virginia rivers based on data accumulated monthly from 1986 through 1999. Diatoms dominated the flora during spring, summer, and fall, whereas, other taxonomic categories were more representative when the river flow rates decreased, allowing for a more stable water system and increased residency time within this tidal region during summer and early fall. This summer/fall period was associated with increased water temperatures, higher productivity rates and chlorophyll levels, increased total phytoplankton abundance and species diversity. The major components of the summer …


Correction [To Maurakis And Grimes Article, V. 54, #3&4] Oct 2004

Correction [To Maurakis And Grimes Article, V. 54, #3&4]

Virginia Journal of Science

This page is a correction to an article by Eugene G. Maurakis and David V. Grimes: Predicting Fish Species Diversity in Lotic Freshwaters of Greece, published in Virginia Journal of Science Volume 54, numbers 3 and 4. Amended table 2a owed to a printing corruption.


Subterranean Loss And Gain Of Water In Mountain Lake, Virginia: A Hydrologic Model, Martin Jansons, Bruce C. Parker, Jacob E. Waller Oct 2004

Subterranean Loss And Gain Of Water In Mountain Lake, Virginia: A Hydrologic Model, Martin Jansons, Bruce C. Parker, Jacob E. Waller

Virginia Journal of Science

Mountain Lake, Virginia is a small, unique, oligotrophic, subalpine ecosystem in the southern Appalachians. Previous studies have disclosed that this lake has manifested periodic prolonged low water levels during the several thousand years of its existence. The most recent low water level occurred during the drought years of 1999-2002. Measurements of lake level, precipitation, and other meteorological data including calculated evapotranspiration in the lake basin from 2/19/02 to 8/31/03 have enabled estimation of net subterranean water losses presumably through cracks between Clinch sandstone boulders and/or the recently discovered deep hole at the northwest end of Mountain Lake. These net losses …


Prescribed Fire Impacts To Amphibians And Reptiles In Shelterwood-Harvested Oak-Dominated Forests, Patrick D. Keyser, David J. Sausville, W. Mark Ford, Donald J. Schwab, Patrick H. Brose Jan 2004

Prescribed Fire Impacts To Amphibians And Reptiles In Shelterwood-Harvested Oak-Dominated Forests, Patrick D. Keyser, David J. Sausville, W. Mark Ford, Donald J. Schwab, Patrick H. Brose

Virginia Journal of Science

As part of a larger study examining the role of prescribed fire in regenerating upland oaks (Quercus spp.), seasonal prescribed burns (winter, spring, summer, and unburned control) were applied to first-stage shelterwood-harvested stands on Horsepen Wildlife Management Area in the Virginia Piedmont in 1995. Because fire impacts are poorly documented for herpetofaunal communities, we surveyed these stands in 1996 capturing 133 individuals of ten species during over 12,720 pitfall trapnights. We found no significant differences in relative abundance of Eastern Red-backed Salamanders (Plethodon cinereus) (P = 0.26), American Toads (Bufo americanus) (P = 0.93), …


Identifying Sources Of Fecal Pollution In The Roanoke River, Roanoke County, Virginia, J. Brooks Crozier, Brian Clark, Holly Weber Oct 2002

Identifying Sources Of Fecal Pollution In The Roanoke River, Roanoke County, Virginia, J. Brooks Crozier, Brian Clark, Holly Weber

Virginia Journal of Science

Antibiotic Resistance Patterns (ARPs) of Enterococcus spp. were used as a phenotypic fingerprint to compare and categorize unknown-source isolates in an impaired segment of the Roanoke River, Roanoke County, Virginia. Antibiotic resistance analysis (ARA) of enterococci has been effectively used to differentiate among sources of fecal contamination in many geographic regions in the United States. Enterococcus spp. were used as a fecal indicator in a library consisting of 1,562 known-source isolates. Two-way analysis indicated that approximately 95% of the unknown-source isolates collected were of animal origin. A 3-way analysis indicated that 61% of the unknowns were of livestock origin while …


Environmental Factors Contributing To The Disaggregation Of A Colonial Cyanoprokaryote And Its Influence On Picoplankton Abundance Within Lake Joyce, Virginia, Lewis F. Affronti Jr., B. Thomas Duquette Jan 2002

Environmental Factors Contributing To The Disaggregation Of A Colonial Cyanoprokaryote And Its Influence On Picoplankton Abundance Within Lake Joyce, Virginia, Lewis F. Affronti Jr., B. Thomas Duquette

Virginia Journal of Science

A colonial cyanoprokaryote, Aphanocapsa holsatica and autotrophic picoplankton abundance were monitored weekly over a two year period in Lake Joyce, Virginia. Significant differences were observed in both the cyanoprokaryote and picoplankton abundance over the study period and an inverse relationship was observed between these two plankton groups. Disaggregation of colonies was shown to contribute to picoplankton populations where water temperature and precipitation input apparently trigger colony dispersion. This relationship is suggested to occur in other aquatic habitats. Results of this work and its implications for ecosystem dynamics are discussed.


Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware Apr 2001

Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware

Virginia Journal of Science

On December 23-25, 1998, a major ice storm struck southeastern Virginia. The storm-deposited glaze ice felled trees and limbs, causing a power outage and highway blockage. Between February and April, 1999, we recorded occurrence, severity, and type of damage to trees over 2.5 cm dbh in nine mostly gently sloping plots in Matoaka Woods at the College of William and Mary. Frequency and severity of damage varied with species and with size of trees. Canopy damage occurred in 75% of large Fagus grandifolia trees, but in only 6% of small Sassafras albidum stems. As a group, small (2.5 to 15 …


Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall Apr 2001

Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall

Virginia Journal of Science

Trachelomonas species from Lake Kilby, a reservoir lake in southeastern Virginia are described with supportive electron micrographs. The most abundant Trachelomonas species wereT. hispida and T. volvocina. Other members of the Euglenophyceae occurring in this lake are identified.


Effects Of Collection, Transport, And Redeployment Methods On Natural Mortality Of Rangia Cuneata (Mactridae) Used In Biomonitoring Studies, Eugene G. Maurakis, David V. Grimes, William C. Gretes Jan 2001

Effects Of Collection, Transport, And Redeployment Methods On Natural Mortality Of Rangia Cuneata (Mactridae) Used In Biomonitoring Studies, Eugene G. Maurakis, David V. Grimes, William C. Gretes

Virginia Journal of Science

Sporadic, high mortality in test populations of wedge clams (Rangia cuneata) has limited the potential for using this otherwise desirable test organism in biomonitoring studies. To determine whether high mortality was due to ontogenic or experimental variables, a two-phased study was conducted. In phase I, mortality of collected and re-deployed wedge clams, subjected to varying transport conditions, was determined at 7, 14, 21 and 60 days re-deployment. The use of three transport times (1, 2, 3 hr.), two vehicle conditions (open, closed) and three transport treatments (open, closed, iced containers) yielded 18 test groups. Individual test group mortalities …


Production Of A Novel Copper-Binding Ligand By Marine Synechococcus (Cyanobacteria) In Response To Toxic Concentrations Of Copper, Arunsi C. Brown, Andrew S. Gordon Jan 2001

Production Of A Novel Copper-Binding Ligand By Marine Synechococcus (Cyanobacteria) In Response To Toxic Concentrations Of Copper, Arunsi C. Brown, Andrew S. Gordon

Virginia Journal of Science

Marine Synechococcus spp. are extremely sensitive to copper toxicity. Some strains have been shown to produce high-affinity, extracellular ligands of unknown structure which form complexes with free cupric ion. They are also known to produce metallothioneins (MT) in response to cadmium and zinc stress. In the present study, marine Synechococcus PCC 73109 (Agmenellum quadruplicatum BG-1) (Van Baalen) was exposed to three concentrations of CuSO4 for various times. Size exclusion chromatography, atomic absorption spectrophotometry, and reverse phase HPLC were used to isolate an intracellular copper binding ligand of low molecular weight (< 6,500 Da). The ligand was detected after exposure to ≥ 8 μM CuSO4 for 2 hr in BG-11 medium. …


Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Historical Sections, Gary Radice, Mary K. Boggiano, Mark Desantis, Peter Larson, Joseph Oppong, Matthew Smetanick, Todd Stevens, James Tripp, Rebecca Weber, Michael Kerckhove, Rafael De Sá Oct 1999

Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Historical Sections, Gary Radice, Mary K. Boggiano, Mark Desantis, Peter Larson, Joseph Oppong, Matthew Smetanick, Todd Stevens, James Tripp, Rebecca Weber, Michael Kerckhove, Rafael De Sá

Virginia Journal of Science

Reconstructing three dimensional structures (3DR) from histological sections has always been difficult but is becoming more accessible with the assistance of digital imaging. We sought to assemble a low cost system using readily available hardware and software to generate 3DR for a study of tadpole chondrocrania. We found that a combination of RGB can1era, stereomicro­scope, and Apple Macintosh PowerPC computers running NIH Image, Object Image, Rotater, and SURFdriver software provided acceptable reconstruc­tions. These are limited in quality primarily by the distortions arising from histological protocols rather than hardware or software.